S.B.K
Math 7B
April 27, 2010 Big Idea Negative numbers help us to model many real world situations. Essential Question #4: How do I multiply and divide integers?
Notes from Class: When multiplying integers, if there is even number of negative numbers, the answer is positive. If there is odd number of negative numbers, the answer is negative.
Problem 4.4 Dividing Integers A. 1. Complete the multiplication sentence -5×6 = ?:
-5 × 6 = -30. Since it's negative multiplied by positive, the answer is negative. 2. Write two division sentences that are equivalent to the multiplication sentence you found in part 1:
-60 ÷ 20 = -30
-120 ÷ 40 = -30 B.1. Complete the multiplication sentence -8×-4 = ?:
-8 × -4 = 32 Negative multiplied by negative is positive. 2. Write two division sentences that are equivalent to the multiplication sentence you found in part 1:
64 ÷ 2 = 32
-64 ÷ -2 = 32 C. Write a division sentence that solves each problem: 1. ?×12 = -132:
-132 ÷ 12 = -11. In order to solve a multiplication problem with division, switch the numbers around. 2. -8×? = -56:
-56 ÷ -8 = 7 3. ?×-4 = 132:
132 ÷ -4 = -33 4. 5.2× ? = -8.84
8.84 ÷ 5.2 = 1.7 D. Write a division or a multiplication sentence that solves each problem: 1. ? ÷ -3 = -8:
-8 × -3 = 18. In order to solve a division problem with multiplication, switch the numbers around. 2. 91 ÷ ? = -7
91 ÷ -7 = -13 3. ? ÷ 11 = -17:
11 × -17 = -187 4. -19.95 ÷ ? = 9.5:
-19.95 ÷ 9.95 = -2.1 Problem 4.4 Follow Up 1. Find each quotient: a. -121 ÷ 11
-121 ÷ 11 = -11. Negative divided by positive is negative. b. 121 ÷ -11
121 ÷ -11 = -11 c. -96 ÷ -4
-96 ÷ -4 = 24. Negative divided by negative is positive. d. 96 ÷ 4
96 ÷ 4 = 24. Positive divided by positive is positive. 2. a. Find 18 ÷ 3
18 ÷ 3 = 6 b. How does your answer from part a help you find -18 ÷ 3, 18 ÷ -3, and -18 ÷ -3?:
The answer to these problems is the same number, but for -18 ÷ 3 and 18 ÷ -3 it’s negative instead of positive.
S.B.K
Math 7B
April 27, 2010
Negative numbers help us to model many real world situations.
Essential Question #4: How do I multiply and divide integers?
Notes from Class: When multiplying integers, if there is even number of negative numbers, the answer is positive. If there is odd number of negative numbers, the answer is negative.
Problem 4.4 Dividing Integers
A. 1. Complete the multiplication sentence -5×6 = ?:
-5 × 6 = -30. Since it's negative multiplied by positive, the answer is negative.
2. Write two division sentences that are equivalent to the multiplication sentence you found in part 1:
-60 ÷ 20 = -30
-120 ÷ 40 = -30
B.1. Complete the multiplication sentence -8×-4 = ?:
-8 × -4 = 32 Negative multiplied by negative is positive.
2. Write two division sentences that are equivalent to the multiplication sentence you found in part 1:
64 ÷ 2 = 32
-64 ÷ -2 = 32
C. Write a division sentence that solves each problem:
1. ? × 12 = -132:
-132 ÷ 12 = -11. In order to solve a multiplication problem with division, switch the numbers around.
2. -8 × ? = -56:
-56 ÷ -8 = 7
3. ? × -4 = 132:
132 ÷ -4 = -33
4. 5.2 × ? = -8.84
8.84 ÷ 5.2 = 1.7
D. Write a division or a multiplication sentence that solves each problem:
1. ? ÷ -3 = -8:
-8 × -3 = 18. In order to solve a division problem with multiplication, switch the numbers around.
2. 91 ÷ ? = -7
91 ÷ -7 = -13
3. ? ÷ 11 = -17:
11 × -17 = -187
4. -19.95 ÷ ? = 9.5:
-19.95 ÷ 9.95 = -2.1
Problem 4.4 Follow Up
1. Find each quotient:
a. -121 ÷ 11
-121 ÷ 11 = -11. Negative divided by positive is negative.
b. 121 ÷ -11
121 ÷ -11 = -11
c. -96 ÷ -4
-96 ÷ -4 = 24. Negative divided by negative is positive.
d. 96 ÷ 4
96 ÷ 4 = 24. Positive divided by positive is positive.
2. a. Find 18 ÷ 3
18 ÷ 3 = 6
b. How does your answer from part a help you find -18 ÷ 3, 18 ÷ -3, and -18 ÷ -3?:
The answer to these problems is the same number, but for -18 ÷ 3 and 18 ÷ -3 it’s negative instead of positive.